


Family Ends With Blood

by Sara_Ellison



Category: Supernatural
Genre: Blood Drinking, Bloodplay, D/s, Demon Dean Winchester, Incest, Knifeplay, M/M, Multi
Language: English
Status: Completed
Published: 2014-10-06
Updated: 2014-10-06
Packaged: 2018-02-20 02:37:38
Rating: Explicit
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 8,311
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2411882
Author URL: https://archiveofourown.org/users/Sara_Ellison/pseuds/Sara_Ellison
Summary: <blockquote class="userstuff">
              <p>Once an addict, always an addict. It was easier not to drink demon blood when Sam's brother wasn't a demon.</p>
            </blockquote>





	Family Ends With Blood

**Author's Note:**

> Another hiatus fic posted in the last hours before the season premiere, sure to be thoroughly Jossed.

Sam is shaking. He's trying to keep calm, trying to keep his breathing even. It's only like the 200th time his brother has died in his arms, and he's come back from it before. Sam gets everything set up, does the ritual, says the incantation on autopilot—it's almost embarrassing, that he knows by heart how to summon the King of Hell.

He's done everything right, he knows he has. Crowley is just being an ass, taking his sweet time showing up the one time Sam really, _really_ needs him. He's keeping Sam waiting just to be contrary.

"Too late, Sammy," Dean says from the doorway, and Sam just about jumps out of his skin, spinning around so fast he nearly falls over. "You don't need to summon him for this one." He's leaning against the doorway, totally casual, looking a little smug. _Jerk._

"You were dead!" Sam blurts. "How—" He catches sight of Crowley, lurking in the hallway behind Dean, and gapes at him. "He brought you back on his own? Why?"

Crowley shrugs, stepping past Dean into the dungeon. "I didn't do a thing. Didn't need to."

Sam narrows his eyes, staring from the demon to his brother. "You were dead," he says carefully. "I know you were. You were stabbed through the chest, and you died. In my arms. Again. Not the first time that's happened, Dean, but usually when you come back, there's a good reason for it, like an angel brought you back."

"Not this time," Crowley says, smirking.

Dean rounds on him. "Shut up, Crowley!" he snaps. "You're not needed here! Go back to Hell."

"Mind your tone, boy," Crowley says softly, and—by rights, Dean should have hit him. Any excuse to go after Crowley has always been good enough, and what with how murderous he's been in general lately, Sam cannot process the way Dean just immediately subsides and stands there with his hands loose at his sides.

"There's something different about you," Sam says aloud. "What did Crowley do to you?"

Crowley raises his hands in an exaggerated gesture of innocence. "I told you, I didn't lay a finger on him! Or in him. It was all the Mark."

"The Mark?" Sam repeats. "The Mark brought you back?" He studies Dean, eyes narrowed. There's something off about him, something about the way he's standing. He's a little too still, a little unnatural. There's no motion to him at all, no hint that he's actually alive except that he's standing up and looking at Sam. His chest doesn't even rise and fall when he breathes.

Which he doesn't do. He isn't breathing. Sam's blood turns to ice. "You're not alive," he breathes.

Dean shrugs. "Depends on your definition of alive."

"What are you?" Sam demands. He reaches for the demon blade—he had it with him when he tried to summon Crowley, just in case he had to use it. "What have you done with Dean?"

"Show him, Dean," Crowley says gleefully. He's all but rubbing his hands together in delight, and Sam feels the bottom drop out of his stomach.

The thing pretending to be Dean blinks, slowly. When his eyelids lift, there's black void beneath, the green eyes Sam has known all his life swallowed up by darkness. He chokes on air when he tries to breathe. "What—" he gasps. "What did you do to him, Crowley?" He's dimly aware of Ruby's knife in his hand, but his palm is slippery with cold sweat and he can't seem to grip it right, and he's shaking enough that he's not sure he could even attack the demon. Either of them.

"How many times do I have to say it, Moose? This wasn't my doing," Crowley says. "Just a happy accident."

"Enough," Dean says. "Please. Crowley, can you let me talk to my brother alone?" He blinks again, and his eyes go back to normal, the color so close to Sam's own.

Crowley shrugs. "As you wish. You know where to find me when you're done." He vanishes, leaving behind a scent of sulfur.

Sam swallows hard. Dean is just looking at him, waiting for him to say something, but Sam can't think of what words to offer, can't imagine what he could possibly say to fix this. "Dean," he says, and his voice cracks.

"It's okay, Sammy," Dean says. "I'm still me. I'm still your brother."

"Don't call me Sammy," Sam says, automatic. He feels disconnected; his mind is floating somewhere above and behind his actual brain.

"Okay," Dean says, but he looks hurt. He's faking it, he's got to be. Demons don't have feelings to get hurt. Do they?

"You don't have a soul," Sam murmurs aloud. "I remember what that feels like."

"I know," Dean says. "But that's not quite true. This—" He gestures vaguely at himself. "Is my soul. Or used to be, I guess. I'm not like you were, when you were walking around all empty while the real Sam was downstairs. I'm the real me."

Sam shakes his head. "You're a demon. You're not the Dean you used to be."

Dean tilts his head, just a fraction. "How do you define what makes me me?" he asks, sounding for all the world like a philosophy professor. "I have all my memories, all my experiences, all my feelings—which is more than could be said for Robo-Sam. Just because my eyes are black, suddenly I'm a whole new person? Hardly anything's changed, Sammy."

"Yeah?" Sam says quietly. "You think Cas will agree with that?"

Dean goes very still for a fraction of a second, and Sam might not have noticed if he didn't know his brother so well. Then he shrugs and says, "Cas liked Meg just fine. The fact that she was a demon didn't seem to stop him from wanting to make out with her." There's just a touch of bitterness to his tone.

Sam's eyebrows climb toward his hairline. "That's the example you want to follow? You're a good demon as long as an angel wants to bone you?" He almost wants to laugh—if this, of all things, is what it takes for Dean to finally admit his more-than-platonic feelings for the angel, then Fate needs to work on her sense of humor. Come to think of it, he's met the bitch, and she really does.

Dean's ears go red at the tips. "That's not—I don't—what—no!" he splutters. "I never said anything about—why would you even say that, Sam?"

Okay, clearly this isn't the right track. The mere suggestion of kissing Cas sends Dean into a reactionary spiral. Sam laughs, short and a bit forced, trying to defuse him, and after a moment, Dean relaxes. He doesn't smile, exactly, but he looks a lot less angry. "Dean, I'm just kidding," Sam says.

Dean smiles a little then, kind of a smirk, not very kind. "Bitch," he says. It's almost right.

"Jerk," Sam replies automatically. Still forced.

Dean shifts his gaze a little, directing his smirk at the knife still clutched in Sam's slightly sweaty, slightly trembling hand. "You gonna use that, or what?"

Sam blinks. He'd actually forgotten he was holding it. "Um...are you gonna give me a reason to need to use it?" When it comes down to it, he really doesn't want to stab Dean with the demon blade. Even if he is a demon. Because he's right, really, Sam can't keep refusing to admit that. He's still Sam's brother.

Dean half-shrugs, stepping closer to Sam. Weirdly coy. "About 20 trillion reasons," he says.

 _What?_ "What?" Sam says. Why is Dean looking at him like that? It's making Sam uncomfortable in unfamiliar ways. He almost wishes Dean would put the black eyes back on, so he wouldn't have to read whatever it is in his brother's eyes. "How did you come up with that number, Dean?"

"Approximate number of red blood cells in my body," Dean says. He grins up at Sam, too close. "Come on, Sammy. Don't tell me you haven't thought about taking a little sip of me."

Sam recoils like Dean is a snake. "Jesus Christ, Dean!" he blurts. "What are you trying to do?"

"Don't you miss it?" Dean says. "Don't you miss the power you used to have? Remember what you could do with just a few drops. Remember Ruby? Remember how you used to cut her—"

Sam doesn't think, he just moves, shoving his brother back with an arm across his throat. Dean doesn't even try to fight it, just laughs as his back hits the wall. "Of course I remember," Sam hisses. He can't see straight. "Every fucking time I meet a demon. I think about it every damn day. I'm an addict, Dean, that's what it means. You never stop being tempted. But you can't give in."

Dean grins. He tries to say something, but Sam's arm across his throat is cutting off his air, and this is usually the point where Sam would let up but he can't kill Dean like this. Not now. He's a demon. He's already dead. Sam can't do him any real harm by strangling him, and Dean is still just grinning at him like it's all a big joke, and he slowly raises an arm over Sam's, brings his hand to his mouth and sinks his teeth into the meat of his palm.

The smell hits Sam like a nuclear missile. No, it's not a smell, per se; demon blood smells just like human blood, for the most part, plus sulfur, but that's not what gets him where he lives. It's something else, some kind of pheromone maybe, something unquantifiable. The scent of power, of desire, of _need_. A whole jumble of words try to cram out of Sam's mouth at once, most of them curses, resulting in a strangled noise. There's blood welling up from Dean's hand a scant inch from Sam's nose, from his _mouth_ , and there's scarlet smeared all over Dean's teeth and somehow in the heat of everything Sam's lizard brain gets confused over whether he wants the blood from Dean's hand or the blood on his lips, and he crushes his mouth against his brother's, his tongue sweeping over Dean's teeth.

The blood tastes better than Sam remembers, because this isn't some stunt demon number three, this isn't Ruby who was always playing him from the start, this is _Dean_ who's had his back since day one, who's always been there, who's made it his personal quest to make sure Sam always got what he needed. It tastes fresh, and hot, and exciting. It's always been exciting; his favorite time to drink from Ruby was when they were both naked and hot for each other, and his body is responding from long-remembered habit. He shoves a thigh between Dean's legs, and he's shocked to find his brother's erection matching his own, but not shocked enough to stop from grinding against him, thrusting against Dean's hip as his tongue invades Dean's mouth. He's licked all the blood from Dean's teeth now, but he's not gonna stop, not when his brother's mouth is hot and wet and he kisses like _that_ , not when the friction against his cock is exquisite, Dean's hips gyrating in counterpoint to his own.

Sam's not gonna stop, even though he's gonna come in his pants if they keep this up, and Dean's gonna make fun of him like he did when they were kids and Sam had a wet dream, or when they'd be fooling around and Sam would come before he meant to, even though Dean was never that far behind. They'd stopped doing things like that when Dean had gotten self-conscious enough to say _Cut it out, Sammy, that's gay_ and Sam has missed this, God, not even the demon blood but just getting off with his brother, knowing that no matter how much Dean laughed at him, it would never hurt as much as anyone else.

Dean moves his arms to wrap around Sam's shoulders, and Sam thinks for a second that it's an embrace, that Dean is remembering what it used to be like too. Then Dean raises a leg and hooks it over Sam's hip, and Sam realizes it's just for balance. His next thrust shoves the bulge in his jeans back under Dean's, right up against his ass, and his breath catches in his throat. He's suddenly desperate and he breaks away, the forgotten knife clattering to the floor somewhere. He gives Dean a shove to keep him against the wall as he grabs at his brother's jeans, yanking them open, gets his hands under the waistband of Dean's underwear and shoves it all down his legs.

Dean's hands are at Sam's fly, and as he gets Sam's cock out of his pants there's a fresh well of blood from the hand he bit, Sam can smell it, and he moans aloud. He gets his hands under Dean's thighs and hoists him up like he weighs nothing because the blood makes him _strong_ and he pins Dean against the wall with his body as his brother reaches down and grabs Sam's dick again, guiding it as he rocks his hips down to meet Sam's thrust and impales himself.

Sam gasps as he buries himself in the heat of Dean's body, the slide of flesh too dry and too tight, pain blurring into pleasure. "Fuck," he says, his fingers digging into the meat of Dean's ass, sweat making his grip precarious. Dean clenches around him and laughs, hitching his hips back with his heels digging into Sam's ass, and Sam resettles his hands and thrusts, hard, stars bursting in his field of vision. " _Fuck_ ," he says again, "Dean!"

"Yeah," Dean says hoarsely. "'S good, right? Tastes good? You want some more, Sammy?" He doesn't wait for an answer before he shoves his hand against Sam's mouth, the slow trickle of blood electric on his tongue. Sam sucks at the bite, worries at it with his own teeth so the flow increases and he gulps it down, the power flooding straight through him, infusing his muscles with iron and his blood with napalm. Dean is moaning aloud, his other hand shoved between them to jerk himself off, and if Sam is gonna be honest with himself in this moment when he's balls-deep in his brother and drinking his demon blood right out of Dean's flesh, if he's gonna be honest then he has to admit he's always loved the noises Dean makes when he's getting off, whether it was with Sam or overheard with someone else or even on his own. When they were kids, even after they'd stopped fooling around together, overhearing Dean masturbating would always turn Sam on enough that he had to jerk off too, and he would usually come to the sound of Dean's orgasm.

"Fuck, Sam," Dean pants, his hand blurring slick on his cock. "Fuck, right there, fuck, Sammy, yeah..." His head tips back on a long moan, something raw torn from his core, and Sam comes like a seismic event, erupting from the inside out and spilling over. Dean screams his own orgasm, spurting all over Sam's shirt, and Sam can't really find it in him to be mad about that right now when he's still shuddering with aftershocks, still holding Dean up while he gets his feet back on the floor. He pulls out and leans against him, breathing hard. Dean still isn't breathing at all.

"That was fun," Dean drawls. His eyes are black again, just for a moment, before he recovers control. Sam steps back from him, licking his own teeth for the last traces of blood as he comes down from the high of—whatever that was. God, what was that? He watches his brother, the demon, pick up his pants from the floor and step back into them before sauntering out of the room.

Sam's brain seems to be having trouble getting back into gear, wrapping around what just happened. He's fallen off the wagon, big time. He fucked up. He shouldn't have drunk Dean's blood. He shouldn't have fucked him. God, why did he fuck his brother? "Dean?" he calls, weakly, because apparently it's still his hardwired instinct to reach for Dean when he's in trouble, even when Dean is the one causing it. Of course, Dean doesn't hear, and Sam wills his legs to move and follow him, belatedly zipping up his pants.

He catches up to Dean just outside the living room, where there's a devil's trap etched into the floor of the corridor, which Dean evidently forgot about or didn't notice, because he's standing in the middle of it looking murderous. He's stomping his feet ineffectually on the floor as though he can break the trap that way. "Sam," he whines. "Lemme out."

Sam scratches a break in the circle without questioning it. He realizes too late that having Dean in the trap would have been a good opportunity to talk, but what's done is done. He follows Dean into the living room, watches him flop down on one of the couches, seats himself on another one. "Dean," he says quietly. "What was that?"

"Devil's trap, Sammy," Dean says, rolling his eyes.

"No, I mean before that," Sam says, annoyed. Dean knows damn well what he means. "What just happened?"

Dean sighs. "I'm a demon, Sam. I figure it's pretty much my job to turn you to the dark side." He shrugs. "It doesn't give me any particular pleasure. You're still my brother. I wish it didn't have to be this way."

Sam glances down at his shirt, streaked white with Dean's come. "You seemed to be enjoying it from where I was standing," he says wryly.

That obnoxious smirk makes a reappearance. "Okay, yeah, it was kinda fun," Dean admits. "You liked it too, though, far as I could tell."

Sam feels his face heat and glances away. "What are we gonna do?" he mutters.

"More of this?" Dean suggests. "You can keep drinking my blood. I know you crave it. And the sex wasn't bad either."

"This isn't you, Dean!" Sam says. "The old Dean never would have been so cool with—with what we just did! You would have been all, _Sam, that's gay,_ and we never would have gotten as far as a handjob, much less..."

"Much less full-on anal," Dean supplies, and Sam blushes harder. Dean kind of flinches a little then, at nothing that Sam can see.

"Are you sore?" he askes, and Dean half-nods. "Sorry," Sam says.

"It's a good sore," Dean replies.

Something twigs in the back of Sam's memory, something about flinching...he narrows his eyes and mutters, " _Christo_."

Dean's whole body jerks, his eyes going black. "Ow! Fuck!" he yelps. "Damn it, Sam! That's not funny!"

Sam snickers. "Kind of is," he says. " _Christo_."

Dean flails again. "That _hurts_ ," he snarls. "My ass is sore from your monster cock, you neanderthal, stop making it worse!"

"Or what?" Sam asks.

Dean leaps at him, catching him off-guard, knocking Sam back on the couch and grabbing him by the throat. "Or I'll rip your tongue from your mouth," he hisses.

Sam struggles to get leverage to throw Dean off him, but the demon is strong. Fighting for air, he gasps, " _Exorcizamus—_ "

Dean howls wordlessly and flings himself backward, cowering against the arm of the couch. "No!" he gasps. "Please don't, Sam, you wouldn't, I'm your brother, please don't send me back to Hell!"

That brings Sam up short. He hadn't thought about that, somehow—that even though Dean is kind of alive and walking around, he would still be pulled back to Hell on a regular basis, and that couldn't be much more fun for a demon than it would be for a mortal soul. Especially not when Dean already has his own memories of being tortured down there. "Sorry," Sam says. "I'm sorry, Dean. I won't."

Dean is still huddled up in the corner of the couch, looking at Sam like he hadn't even when Sam was holding a demon-killing knife. _Shit._ Sam reaches out slowly, making sure Dean can see his movements, and lays a hand on his brother's shoulder. "Hey, it's okay," he says. "It's gonna be okay. I'm the last person that's gonna send you back there."

"Can I trust you?" Dean asks flatly. "You can hurt me with a single word. You can send me to Hell if I let you get the words out. Fuck, since I let you drink my blood, you can kill me with your brain."

"You're my brother," Sam says by way of answer, then, after a moment, "I'm gonna save you."

The look in Dean's eyes is momentarily earnest, almost grateful, but it's quickly shuttered behind another smirk. "Yeah? Save me from what, exactly?"

"Hell," Sam says. "Being a demon. Being Crowley's bitch. I'm not the only one who can exorcise you, you know. I'm not the only one who could kill you. Any angel, if they got it into their head—"

"Any angel coulda killed me when I was human, too," Dean points out.

"Maybe they wouldn't have had reason to," Sam says. "Now, any random angel sees you, they just see a demon that needs smiting. You're more vulnerable now, Dean. We can fix this." He takes a breath, trying to stifle the memories of how unpleasant the last attempt had been. "I can cure you."

"No, you can't," Dean says immediately. "You almost died last time, remember? Ended up with Gadreel inside you? Kinda how we ended up here?"

"I remember," Sam says. "It was the Trials that almost killed me. I'd already completed two of them, and the third one would have killed me. This would just be curing a demon. We'll both come out of it just fine." He sounds more confident than he feels.

Dean is quiet for long enough that Sam is starting to think he's not going to say anything when finally he whispers, "Okay."

"Okay?" Sam repeats. Part of him never expected Dean to acquiesce. "You want to try?"

Dean half-shrugs in the way he does when he's trying to pretend he's more cool about something than he is. "Yeah. Let's do it."

"Okay." Sam is suddenly terrified by the prospect—not for himself, but for Dean. What if, somehow, this goes wrong and he kills his brother for good? He doesn't want to lose him again...but if he doesn't try, Dean may as well be lost anyway.

*****

"Bless me, Father, for I have sinned." The words echo faintly in the empty confessional; there's no priest, no one to hear him...at least, no one visible. No one mortal. The church is abandoned, not as run-down as the last time Sam did this, but he had to break in nonetheless. Add that to his list. He swallows, his throat suddenly dry. "It's been...I don't remember how long it's been since my last confession."

He shuts his eyes. He knows where to start; he didn't have to ask Dean this time. His heart is pounding, hard enough that it jolts his body with each beat. "I fucked my brother. I drank his demon blood, and I enjoyed it."

He waits for God to strike him down in punishment, for the ground to open up and swallow him back down to Hell, for crushing remorse to overwhelm him. There's nothing, only the throb of his pulse roaring in his ears. He whispers, "I want to do it again," and can't hear himself over his own blood.

It's not his own blood though, there's demon blood in there too, Dean's blood. They've always had each other's blood, always been a part of each other, always been under each other's skin. Maybe now it's just a little more literal than before.

Sam opens his eyes. The darkness swims and buzzes for a moment before settling, the faint light filtering through the boarded-up windows barely illuminating the inside of the cramped booth. He exhales, and continues. "I have sinned," he murmurs. "I have lied..."

By the time he's finished listing his sins, his legs are stiff from prolonged immobility, and he feels no different than he did when he started, save for a dry tongue and a sore jaw from whispering so long into the darkness. There's no weight lifted from his shoulders, no sense of absolution, no one to tell him how many Hail Marys to say to wipe his slate clean. He sighs, stands and stretches and tries to tell himself that it's nothing to worry about, he's done it right, it's going to work this time.

Dean is waiting right where Sam left him when he gets back to the bunker. He's lounging in the armchair, evidently relaxed, but there's tension in the lines of his body that Sam knows is due to the devil's trap painted on the floor beneath him. Dean had bitched and moaned about that, but Sam had insisted. "This way, Crowley won't be able to abduct you before I get back," he had said, because of course Dean wouldn't run of his own free will, not after he'd assured Sam he wanted to be cured.

He jumps to his feet when Sam appears. "Hurry up and let me outta here, I gotta pee," he says. His eyes are black again, making him impossible to read.

Sam frowns, considering. He heads to the kitchen and pulls an empty Gatorade bottle out of the recycling bin.

"You're kidding," Dean says. "What if I have to go number two?"

Sam tosses him the bottle carelessly. "You don't need to breathe. Why would you have to go to the bathroom?"

Dean scowled but didn't answer, settling back into his chair, setting the bottle on the floor. "Let's get this over with, then," he says.

Sam nods, opening the Men of Letters' old kit. The syringe is old, glass and metal with a thicker needle than Sam would like, but it does the job, and he clenches his fist to raise a vein and slides the needle in.

"Ready?" Sam asks.

"Just do it," Dean says. He tips his head to the side, exposing his neck. For a moment, Sam is tempted to bite him, vampire-style, and drink more of his blood, but he shoves those thoughts down and pierces Dean's skin with the needle, injecting him.

Dean shudders as Sam pushes the plunger down, his eyes flickering to black and staying that way as Sam steps back, outside the radius of the devil's trap, and begins reciting the modified exorcism. That makes Dean shudder harder, writhing in his seat, but he keeps his jaw clenched and doesn't say a word until Sam is finished. He sags back against the chair then, visibly sweating, and says, "How long until the next one?"

"An hour," Sam reminds him. "You, uh...want a magazine or something?"

Dean shakes his head. "No, thanks. Actually..." His eyes are green again with a blink. "When I'm bored, I'd rather jerk off." One of his hands falls casually into his lap, palming his crotch. "Wanna lend a hand, Sammy?"

Sam flushes. "No." He's lying, of course; he wants to do all kinds of things to Dean, but he has a feeling that if he sins again, the benefit of having gone to confession will be erased. He stalks over to the couch to hide his annoyance and frustration, trying to convince his half-hard cock of what a bad idea it would be.

They fall into silence, both watching the clock until it's time for the next round. This time, Dean flinches harder from the needle, writhes harder as Sam says the words and grunts in pain. He's panting hard when it's over, and given that he doesn't even need to breathe, that worries Sam.

"I'm good," Dean mutters, black-eyed and glaring. "No problem. You're just undoing in a few hours what it took months to do to me, why should that be difficult for me?"

Sam frowns. "Dean, I'm not judging you for having a hard time with this. It wasn't fun for Crowley either."

Dean rolls his eyes. "Whatever. I'm just saying, we can keep going."

"I know," Sam says. He wasn't going to stop anyway, would have kept curing his brother no matter what, even if he had to chain him up like they had with Crowley.

Dean doesn't struggle against the third injection, only shifting in the chair a bit as Sam's blood diffuses into his veins. He tips his head back as Sam withdraws the needle, eyes half-lidded. His pupils are dilated but his eyes haven't gone demon-black, and as Sam begins to pull away Dean almost lazily grabs the front of his shirt. He tips his chin up, almost challenging before he catches Sam's mouth with his own.

Sam knows he should pull away, but Dean's lips are soft and his tongue is warm. He leans into it, his eyes just beginning to slip shut when a familiar sound of wings makes him jump. He turns, simultaneously horrified and relieved to see Castiel, looking exhausted. "Wait," he says, overriding any more usual greeting he might want to offer, his heart pounding in panic. "I can explain."

Cas' eyes dart from the syringe still in Sam's hand to the devil's trap above Dean's head, finally landing on Dean's face and staying there as his expression turns to one of utter dismay. "Oh God, Dean, what have you done?"

Dean licks his lips slowly, a nervous reflex turned deliberate. "The Mark of Cain turned me into a demon," he says. "You make it sound like I chose this."

"You chose to accept the Mark," Cas says. He makes a dismissive gesture at Sam. "Put away the needle. That's not going to work."

"Well, it's not like I knew this was going to happen!" Dean argues, talking over Sam's protest, "Why not? It nearly worked on Crowley."

"You hadn't been drinking Crowley's blood," Cas says. "You're corrupted. You're just giving Dean his own back, plus your own flavor of corrupted humanity."

Sam is silent, tamping down anger until he can keep his voice level. "You knew," he says to Dean. "You knew my blood wouldn't cure you. Why'd you let me go ahead with it?"

Dean turns his gaze back to Sam with a slow weight that presses on Sam's ribs, stifling his breath. "Got my blood inside you," he says. "Maybe I wanted to feel you inside of me, too."

Sam's face burns. He darts a glance at Cas, who doesn't seem to react to the innuendo, but if he can tell Sam drank Dean's blood then surely he knows, he must know what else they did, he must know how much more corrupted Sam really is...

Castiel steps forward and scuffs his shoe across the outer edge of the devil's trap. "Show me," he says. "Show me what you are now, Dean."

Dean stands up from the chair. Cas doesn't step back, and it puts them right in each other's personal space—no, closer than that, Sam thinks, recalling some random infographic he'd seen online: public space, personal space, intimate space. This is intimate, uncomfortably so, the two of them breathing each other's air—or would be, if either of them needed to breathe—as Dean slowly blinks his eyes black and smirks, sharklike. "What do you think?" he asks. "Does black look good on me?"

"I preferred the green," Cas says, his own eyes narrowed.

Dean's smile vanishes, replaced by something that could almost be called a pout if he weren't a 35-year-old grown-ass demon. "You liked black well enough on Meg."

"You aren't Meg," Cas replies, suddenly soft. "Meg's gone."

Dean looks at him for a second, his eyes draining to green. "You actually..." he murmurs. "Did you love her?"

Cas doesn't answer, and that's answer enough.

"So you can love a demon," Dean says.

"Dean—" Cas says, and somehow fits half a dozen things into the name, makes it sound like _you, human or demon_ and _since the moment I met you_ and _always_ and _anything for you_.

From the way they're looking at each other, Sam honestly thinks they're about to start making out a split-second before Dean turns to look at Sam, and Sam almost jumps because he was pretty sure they'd forgotten he's there. "Sam," he says.

Sam clears his throat. "Yeah, Dean," he says, feeling a thousand kinds of awkward.

"You're my brother," Dean tells him. "I need you. That doesn't change, whether I'm a demon, a vampire, whatever. We look out for each other. Okay?"

"Of course, Dean," Sam says. He wants to ask what exactly Dean means when he says he needs him, but Cas is right there, and even if Sam is reasonably sure the angel _knows_ about him and Dean, he really doesn't wanna say it out loud in front of him.

"Good," Dean says, and he claps Cas on the shoulder in a casual, friendly, not-at-all-homosexual way and steps away from him. "We're all good, then."

Sam gapes at him. "What, that's it?"

Dean shrugs, wandering toward the kitchen. "You're fine with me being a demon, Cas is fine—"

"I'm not fine," Cas interrupts.

Dean turns back to face him, looking annoyed. "Then what was all that just a second ago?"

Castiel frowns. "Dean, the fact that I lo—" He cuts himself off mid-word. "That I care for you doesn't mean I'm going to step back and let you continue..." He gestures vaguely at all of Dean. "It means that I'm going to try to help you."

"Yeah?" Dean raises an eyebrow. "How are you gonna do that, if the demon-curing ritual won't work with Sam's blood?"

Cas chews his lip for a second, thinking. "I don't know," he admits. "But I'll find a way."

"You're going to have to stop biting your lip," Dean says.

Sam blinks, taken aback. "Did you just—"

"—Make a reference to _Fifty Shades of Grey_?" Cas finishes for him.

Sam stares. "You've read that?"

Cas grimaces. "I've had knowledge of popular culture forcibly inserted into my mind without my consent," he says. He glances at Dean. "Although I believe you have the roles reversed. As a demon, your sense of morality has been compromised. You ought to defer to me on matters of conduct."

Dean raises his eyebrows. "Oh, you think so? You're gonna be, what, my handler? My keeper?"

"You do need someone to keep you in line," Castiel tells him. "Between myself and Sam, we should be able to teach you to behave."

Something ignites deep in Sam's gut, a flame mirrored in Dean's eyes. There is something irresistibly compelling about the idea—having Dean under his control, having his blood whenever he wants it, sex whenever he wishes, and Dean would obey him, submit to him...but that isn't right, that isn't what he was for. Demon or not, Dean is Sam's brother, not some toy to be used.

Sam glances at Cas, seeing the same desire in his eyes, paired with a steady determination that reminds him exactly what Castiel is. He is a born commander, a being more powerful than any on earth. If anyone can keep the demon in line, it's him.

"I can't," Sam says. "Cas, I'm not..." He trails off, searching for the words. Cas had called him an abomination, once. It's not his place to be Dean's keeper, or any position of power over him, not when he can be so easily compromised, when an offer of blood or sex can make Sam succumb to his own worst nature. "You're his angel. I'm just..."

"The person who knows him best in the world, even now," Castiel finishes for him. "I can't do this without you, Sam."

Sam gestures helplessly. "I drank his blood—"

"Which makes you stronger," Cas says. "You can control him all the more easily with his blood in your veins."

Dean leans back against the wall, slouching lazily, for all the world as though they're not discussing his fate. "Control me how, exactly?" he asks. "What is it we're talking about here?"

"Domination," Cas says bluntly. "You will submit to me, and to Sam, in terms of your behavior and morality. We will prevent you from acting as do most of demonkind, and in return, we will see to it that your needs are met."

Dean starts to laugh. It's an unpleasant sound, not his amused chuckle or his dry, humorless laugh, but a cruel and mocking snicker. "What needs are those? I don't need to eat or sleep or even breathe anymore. What do you think you can offer me?"

"Maybe need isn't the right word," Sam suggests quietly. "Whatever you call the motivation that makes you spread your legs for me."

Dean's mouth shuts with a snap. "Oh," he murmurs. "That." And that's all there is to it.

*****

They start simple, binding Dean to the bed with the manacles they once used on Crowley, engraved with sigils and devil's traps to keep him from escaping. He writhes against the memory foam mattress, fruitlessly, straining at the chains to see how far they'll give. He's already breaking a sweat, naked skin nearly glowing with it. He's hard, his cock flushed and curving toward his belly, glistening at the tip. Sam wants to devour him.

"Are you ready, Dean?" Cas asks. His voice is quiet, but there's power behind it, a strength that would be intimidating or downright terrifying in other circumstances. Now, though, when he's leaning over Dean with something more than lust in his eyes, Sam feels more kinship to him than fear.

Dean snarls in answer to the question, and Sam expects the next words out of the demon's mouth to be profanity, but he only hisses, " _Please_ ," and spreads his legs wider, as much as the chains will allow. Castiel presses a finger into him then, slick with lube, sinking in to the third knuckle, and Dean moans aloud. "Come on," he says, "more. I won't break, come on, please."

"He's right," Sam says lowly. "He's not a fragile mortal anymore. We can be as rough as we want with him. Don't even really need lube."

Cas glances at him. "He may not need it, but I'm thinking of our comfort more than his," he says, pushing another finger into Dean and twisting them, making Dean's whole body jerk. Sam remembers the dry fuck down in the dungeon and concedes the point.

Cas is working Dean open like it's his job, focused intently on the motions of his hand, stretching Dean's hole around his fingers, and Sam is torn between wanting to watch Dean fall apart with need and studying Cas. His body language is possessive but not threatening; he's not leaning over Dean, just kneeling between his legs and fucking Dean with his fingers, jabbing at his prostate every so often just to make sure the demon is paying attention. It might be the hottest thing Sam's ever seen, Dean so completely at Cas' mercy.

"Enough," Dean whines. "Fuck me already, Cas, please!"

"No," Cas says. "Sam's going to fuck you now." He pulls his hand out and moves around toward the head of the bed, kneeling next to Dean's shoulder, too far for Dean to reach with his mouth although he tries, stretching his neck and flicking his tongue out as though he can bring Cas' cock closer by force of will.

Sam hesitates. He thought Cas would want to go first, but his cock isn't exactly objecting to this turn of events, not when Dean has stopped trying to bend the laws of space to suck the angel's cock and is looking at him like he might die if he doesn't get fucked soon. Then Cas reaches over beside the bed, grabs a knife, and hands it handle-first to Sam. It's not Ruby's knife, not an angel blade, just an ordinary, human-made hunting knife. It won't kill a demon, but it can still cut flesh, and Sam leans forward, covering Dean's body with his own, his weight braced on one hand. He drags the point of the blade up from Dean's sternum along his left collarbone, watches the needle-thin line of red well up, ducks his head to taste it. He takes a second to savor the flood of power, feels it tense his muscles, tighten his skin, harden his cock. He groans aloud, eyes slipping shut, and thrusts blindly, grinding against his brother's groin.

"Sammy," Dean whispers, and it's a comfort and an aphrodisiac and a taunt all at once. He wriggles again, hips angling until the head of Sam's cock is nudging his hole.

"You taste so good, Dean," Sam breathes. He pushes forward, his cock breaching Dean's slick entrance, sinking into him like coming home. He resettles his grip on the knife, opens his eyes and draws a matching slice along the other collarbone, sweeps his tongue over it, thrusts into his brother. "So good."

Cas shifts, moving close enough for Dean to suck him side-on, tongue curling around his shaft. Dean moans against his flesh, his hips rocking to meet Sam's thrusts. Cas makes a soft sound of pleasure, one hand grabbing Dean's hair as the demon mouths at him. "That's good," he says. "Keep doing that, Dean. Good boy."

Dean whimpers, hands jerking in the cuffs, and clenches around Sam. Dean's craving for approval is certainly nothing new, but in this context, somehow, it's like gasoline on a fire, stoking Sam's arousal as surely as the sensation of Dean's body engulfing his cock. Dean;s movements are growing more frantic, almost desperate, and Sam knows that by now Dean would want a hand on his cock, knows he's getting eager to finish. Sam looks up, catches Cas' eye, and the angel nods.

Cas' hand in Dean's hair releases its grip, petting instead, soothing the sting. "You're doing well, Dean," Cas says, his voice almost steady. "You want more, don't you? Do you want to come?" The noise Dean makes, muffled by Cas' cock, is nevertheless unmistakably affirmative. "But you won't come until we tell you to, isn't that right, Dean? Because you're a good boy, and you do as you're told."

Dean whines, loud and long, leaking onto his belly, and clenches up in a way that sends lightning up Sam's cock straight to his brain, stars bursting in his vision and he jerks back, pulling out and grabbing his cock before he comes. "Fuck," he gasps, "Dean, _fuck_." He's so damn close now, his hand moving on his shaft as he knees up beside his brother, meeting Dean's desperately aroused gaze, catching Cas' look of approval as he tenses and comes, spurting across Dean's chest, striping white over the scarlet lines of blood.

Cas pulls back, his cock glistening at the head. Dean licks his lips, red and swollen, and tips his face up toward Sam, silently pleading. Sam falls onto him, crushing his mouth against Dean's, kissing without finesse. His heart is still pounding from his release, his skin flushed and damp, and this kiss is the only thing holding him down onto the surface of the planet. Dean's mouth is nearly slack under his, his tongue moving only slightly against Sam's. It's nothing like the kisses earlier, nothing like the usual Dean. Sam breaks the kiss when he feels like he won't drift out of Earth's gravity well. Dean is looking up at him, his eyes wide and bright. "Sam," he whispers. "I love you."

Sam's breath catches, and he has to take another before he can speak. "I love you too, Dean," he says. "You were so good."

Dean smiles. "Can I come now?"

"No," Sam answers, unhesitating. "Not until Cas says you can." He glances up, finding Cas at the foot of the bed, unlocking the cuffs from Dean's ankles.

"Don't worry," Cas says. "Just keep doing as you're told, and we'll let you come. You've been so good, Dean." He moves between Dean's legs and shoves his thighs up, nearly folding the demon in half. "Are you going to take me as well as you took your brother?"

"Yes," Dean breathes, and he nudges at Sam's shoulder with his head before turning his attention fully to Cas. He gasps as the angel penetrates him, his eyes wide and locked with Cas'. He wraps his legs around Cas' waist as Cas begins to thrust, steady and inexorable. Dean isn't rocking his hips in counterpoint this time—he can't, he has no leverage in this position. He's just hanging on and taking it. "Cas," he whimpers. "Kiss me?"

"Do you think you've earned that, Dean?" Cas asks, his voice as cool as possible given the circumstances. He looks good like this, Sam thinks, with his face flushed and his hair all in disarray.

"No," Dean admits, and he looks like he wants to cry, and part of Sam wants to hit Cas for that. "I haven't. I've pushed you away when I should have kept you close, I've left you when I should have stayed, I—"

"Sshh," Cas soothes him. "That's in the past, Dean. You're going to be good from now on, aren't you? You're going to stay with us now." He kisses Dean, his lips soft on the demon's, slow and sweet in counterpoint to his thrusts.

When he pulls away, Dean whimpers. "Please, I need to come," he begs.

"Soon," Cas promises. "First you need to say it."

"Say what?" Dean whines. "I already said I'll be good."

"Not that," Cas says, his voice rough, and Sam gets it.

"Tell him what you told me," Sam says, and Dean glances at him, startled, then back to Cas.

"I love you," he blurts. "Cas, I—I've always loved you."

Cas lets his eyes fall shut, then, and exhales on a moan. "Sam," he gasps, "give him a hand. You can come now, Dean. Come with me."

Sam reaches between their bodies to wrap his hand around his brother's cock, the flesh hot and iron-hard in his palm. It only takes a few strokes before Dean is crying out and shuddering, spilling over Sam's fingers as Castiel shudders and curses through his own climax. He thrusts through the aftershocks before pulling out, slumping beside and half on top of Dean. "I love you too, Dean," he says. "Always."

Sam watches as Cas slips an arm around Dean's waist, holding him loosely. He sits up, searching around for the key to Dean's shackles, and unbinds his brother's wrists. "Thanks," Dean says absently. He lowers his arms carefully, one finding its way around Cas' shoulders, the other lying open for Sam.

Sam lies down again, and Cas reaches out for his hand—the one still sticky with Dean's come, and Cas brings it to his lips and kisses between Sam's fingers, open-mouthed, sucking the mess away. A sigh escapes Sam, unbidden and unexpected, satisfaction and contentment overpowering him.

He could fall asleep like this, Sam thinks, the three of them in Dean's bed, fucked-out and loved, were it not for the unwelcome voice that intrudes on their afterglow. "Well," Crowley says dryly, "isn't this sweet."

Sam sits bolt-upright, not bothering to try for modesty—there's nothing within easy reach, and that's not as important right now as the asshole demon violating their space. Cas is half-upright, leaning over Dean protectively. "Get out," Sam snarls, and instinctively throws out a hand, closing his psychic grip on Crowley's throat.

Crowley chokes, hands instinctively going to his collar. "Sam," Dean says, "stop it," and Sam inexplicably obeys.

Crowley coughs. "You let him drink from you? Dean, this is not the first time, nor I expect will it be the last, that I question the wisdom of your choices."

Dean shrugs, and smirks. "Yeah, but we had fun. Didn't we, boys?"

Castiel draws back from him slowly. "Yes," he says, dangerously quiet. "We had fun."

"Leave, Crowley," Sam says. His voice doesn't sound like his own. "Dean's not going with you."

"Actually..." Dean stands up and stretches, bending down to give Sam a kiss on the cheek.

"But," Sam blurts. "What about—you promised Cas you would stay with us!"

"Technically, I didn't," Dean says. "You just inferred it. Besides, haven't I told you, Sammy? Demons lie."

It's like a punch to the gut. Sam can't catch his breath, feels like he might puke. He tries to find something to say that might change Dean's mind, but...it's not even really Dean's mind. It's a demon that used to be his brother.

"So, I'll see you around," Dean says, and heads for the door.

Castiel speaks up. "I still love you, Dean," he says.

Dean's step falters, just a little, surely invisible to anyone who didn't know him as well as Sam does. He doesn't turn back, though, just continues out of the room.

Crowley rolls his eyes—Sam isn't sure at what; Cas' declaration of love, or Sam's gullibility, or Dean's attitude—and follows him out. "Do you maybe want to put on some pants?" he calls, then he's gone.

Cas is way ahead of him, dressed before Sam can remember where he left his clothes. "Come on," he says. "We have a demon to hunt."

Sam balks. "No," he protests. "He's my brother."

Cas fixes him with a gaze that brooks no argument. "To any other hunter, he's just a demon that needs to be put down. Don't you think it had better be us who gets to him first?"

He has a point. Sam winces as he stands. "I guess we've got work to do."


End file.
